We have investigated commensurability oscillations (CO's) in the magnetoresistances of stressed rectangular two-dimensional lateral surface superlattices. Devices were realized by shallow etching of holes, arranged on rectangular grids, into GaAs/AlxGa1-xAs heterostuctures. Changing the gate bias on these devices was observed to change the period of the CO's. This phenomenon was predicted by a recent semiclassical theory based on the guiding center-drift concept, and corresponds to the switching of the drift direction in the superlattice as the dominant Fourier component changes. When different Fourier components in the potential were approximately equal, then switching of the drift direction for varying magnetic fields was also observed.
Switching of guiding center-drift direction in asymmetric two-dimensional lateral surface superlattices
PENNELLI, GIOVANNI;
2001-01-01
Abstract
We have investigated commensurability oscillations (CO's) in the magnetoresistances of stressed rectangular two-dimensional lateral surface superlattices. Devices were realized by shallow etching of holes, arranged on rectangular grids, into GaAs/AlxGa1-xAs heterostuctures. Changing the gate bias on these devices was observed to change the period of the CO's. This phenomenon was predicted by a recent semiclassical theory based on the guiding center-drift concept, and corresponds to the switching of the drift direction in the superlattice as the dominant Fourier component changes. When different Fourier components in the potential were approximately equal, then switching of the drift direction for varying magnetic fields was also observed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.